Employees Benefit From Natural Light, Study Finds

THURSDAY, Aug. 14, 2014 (HealthDay News) -- Natural light during the work day may benefit employees by improving their sleep and quality of life, according to a new study.

"There is increasing evidence that exposure to light, during the day -- particularly in the morning -- is beneficial to your health via its effects on mood, alertness and metabolism," study senior author Dr. Phyllis Zee, professor of neurology at Northwestern University Feinberg School of Medicine and director of the Sleep Disorders Center at Northwestern Memorial Hospital, said in a university news release.

"Workers are a group at risk because they are typically indoors often without access to natural or even artificial bright light for the entire day. The study results confirm that light during the natural daylight hours has powerful effects on health," she said.

The study included 49 day-shift office workers -- 22 in workplaces with windows and 27 in windowless workplaces.

Compared with those with little light exposure, workers with more exposure to natural light slept longer and better at night, got more exercise, and had a better quality of life. However, the association seen in the study did not prove a cause-and-effect relationship.

"Light is the most important synchronizing agent for the brain and body," study co-lead author Ivy Cheung, a Ph.D. candidate in neuroscience in Zee's lab, said in the news release. "Proper synchronization of your internal biological rhythms with the Earth's daily rotation has been shown to be essential for health."

The findings highlight the importance of designing offices that provide natural daylight for workers, according to the authors of the study recently published in the Journal of Clinical Sleep Medicine.

"Architects need to be aware of the importance of natural light not only in terms of their potential energy savings but also in terms of affecting occupants' health," study co-lead author Mohamed Boubekri, an associate professor of architecture at the University of Illinois at Urbana-Champaign, said in the Northwestern University news release.

Boubekri said a simple solution is to make sure that employee workstations aren't more than 20 to 25 feet away from outside walls that have windows. "Daylight from side windows almost vanishes after 20 to 25 feet from the windows," he noted.